[% setvar title Undef values ne value %]
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<a name='TITLE'></a><h1>TITLE</h1>
<p>Undef values ne value</p>
<a name='VERSION'></a><h1>VERSION</h1>
<pre>  Maintainer: Richard Proctor &lt;<a href='mailto:richard@waveney.org'>richard@waveney.org</a>&gt;
  Date: 4 Sep 2000
  Mailing List: <a href='mailto:perl6-language@perl.org'>perl6-language@perl.org</a>
  Number: 192
  Version: 1
  Status: Developing</pre>
<a name='ABSTRACT'></a><h1>ABSTRACT</h1>
<p>If you compare a variable that is undefined with something, perl winges.
An undefined value is not equal to a string, it should do the right thing.</p>
<a name='DESCRIPTION'></a><h1>DESCRIPTION</h1>
<p>Perl winges if you compare an undefined value.  This is silly and one often
has to test for the undefined case (and the empty case for == and !=), then
the equality that the programs logic calls for.  If you leave warnings off
perl does the right thing anyway.</p>
<p>Thus:</p>
<pre>  $foo = undef;

  if ($foo ==  1) # should fail the test but not complain
  if ($foo !=  1) # should pass the test, and not complain
  if ($foo eq &quot;bar&quot;) # should fail the test but not complain
  if ($foo ne &quot;bar&quot;) # should pass the test, and not complain</pre>
<p>lt,&lt;,le,&lt;=,gt,&gt;,ge,&gt;= should behave as now, as it is resonable to object
in these cases as the inequality is not well founded.</p>
<p>A comparison between two undefs should (probably) remain an error.</p>
<a name='IMPLENTATION'></a><h1>IMPLENTATION</h1>
<p>No idea</p>
<a name='REFERENCES'></a><h1>REFERENCES</h1>
<p>None yet</p>
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